In a paper for MacHack several years ago, I tried to sort out the possible methods for evaluating claims found on the internet. (`Reliability on a Crowded Net' -- The conference still hosts a PDF of it.) I was primarily interested in claims made on web pages and in chat rooms, and I think the analysis extends pretty well to blogs.

Many people now use Wikipedia as their reference of first resort, however, and I wonder whether my previous analysis applies to it. In the paper, I identify four basic methods for evaluating a claim found on the internet and claim that they are exhaustive. Consider each in relation to the Wikipedia:

Appeal to Reliability involves relying on the reputation of the source. If I read an article on the New York Times website, I give it roughly the same weight as I would an article in the print edition.

It is not entirely clear how reliable the Wikipedia really is. It does have a good reputation. There is also a story to be told about the self-correcting nature of collaborative work. Nevertheless, a wiki will only be as reliable as its most persuasive members. I suspect that its reliability depends on the topic area-- because different topic areas will have different contributors.

Appeal to Plausibility involves assessing whether the general claims even sound like they are in the right ball park. This can be done both in terms of content and in terms of style. I think there is some reason to think that the Wikipedia could be deceptive in this regard. Even where it contains false information, contributors may have preened it to make it sound more plausible.

Suppose an entry contains incorrect information. If people wander through the site and make the entry sound better, even though they do not actually have any special expertise on the subject of the entry, then the entry will be written in a more plausible way than it would be if it were just the original falsities on somebody's personal webpage.

Calibration involves checking the facts where you can and extrapolating: If the source gets things right on matters you can check, then that is some reason to believe that it gets things right on matters you can't. Again, the collaborative nature of the Wikipedia makes this harder. If the things that you can check independently are the things that other people could check, then those things will probably be correct-- someone will have corrected any mistakes. The correctness on those points will fail to be evidence for the correctness on the remainder, if the background knowledge of honest and conscientious contributors runs out where yours does.

Sampling involves checking multiple sources and comparing them against one another. Insofar as one just does a quick Wikipedia lookup, one avoids sampling.

So the basic methods for evaluating credibility all get harder with the Wikipedia. The central issue is the degree to which the collective nature of the Wikipedia can be relied on to be self-correcting. How much is this a reasonable expectation, and how much is this an article of faith?

I've been reading Lauren Slater's Opening Skinner's Box, a popularized discussion of significant experiments in 20th-century psychology. The book is best when it presents facts and background, and worst when it tries to pose philosophical questions. One chapter is about Elizabeth Loftus' work to debunk repressed memories. Loftus points out that there is no plausibly mechanism whereby repressed memories would be stored in the brain.

Slater believes in a repressed memories nonetheless, and mentions Van der Kolk with approval. Der Kolk's view is that "the body keeps score." Anything that is too traumatic to be remembered is stored nonnarratively, to return later as muscle aches or panic attacks. The solution to such problematic, visceral memories is to recover them narratively. Fess up to the traumatic event, and the aches will go away.

So this has me thinking: Suppose that der Kolk is right, that there are separate centers of episodic and visceral memory, and that eliminating bad visceral memories is just a matter of thinking through the story of the traumatic event. There is nothing in such an approach that requires the story you think through to be true. Since there is no episodic memory of the event to compare to the recollection, your body has no way of checking.

I suggest the obvious therapeutic approach: Tell yourself a story about any bad visceral memories that your body has stored up. The beauty is that any story will do, as along as you meditate on it and process it through the narrative parts of your brain. I dub this innovation Bogus Scenario Therapy. A session might go like this:

Me: [In a silly mock-Austrian accent, because it enhances the therapeutic value of balderdash.] Zo, you haff been havink these panik attacks. Tell me about ze aliens from your memories.

Patient: [Lying back on a couch, like in a New Yorker cartoon.] What aliens?

Me: Ze traumatic ones. Ze ones from your memory. Vork mit me.

Patient: Oh. They were grey, I guess.

Me: Excellent. And zeir heads? Big or zmall?

Patient: ...um... big.

Me: [writing down 'big' in my notebook.] Vider zan zeir shoulders?

Patient: ...yes.

Me: And their arms: articulated like a humans?or did zey bend backvards?

Patient: [more confident now.] Backwards.

Me: And vat sounds did zey make?

And so it would go, with me billing hourly for little games of make believe. There would be money in it, if only I could keep a straight face.

At lunch, discussion led to this question: Is the world that 'Rosencrantz&Guildenstern are Dead' is set in the same world that 'Hamlet' is set in?

Thesis: They are the same world. Tom Stoppard took great care in making the events that happen in 'R&G' intersect and overlap events that happen in 'Hamlet'. Stoppard's project requires that the world of his play be the same as the world of Shakespeare's play. Stoppard's play is a brilliant success, so it follows immediately that the two plays take place in the same fictional world.

Antithesis: They are not the same world. Stoppard adds shenanigans that Shakespeare clearly did not have in mind. They reach beyond, and some of them perhaps directly violate, Shakespeare's authorial intention.*

The question puts us in a bind, because both the thesis and the antithesis are plausible. The problem, I think, is that they both presuppose that there is one fictional world picked out by 'R&G' and one picked out by 'Hamlet'. Only on that assumption does it make sense to ask whether the worlds are the same world.

Suppose instead we treat 'Hamlet' as picking out a set of possible worlds; call them the Hamlet-worlds. Similarly, 'R&G' picks out a set of worlds; call them the RG-worlds.**

We can do justice to the intuition behind the thesis by saying that all RG-worlds are Hamlet-worlds.

We can do justice to the intuition behind the antithesis in this way: The Hamlet-worlds are a mixed bag, with some of them having very little detail beyond what is specified in the script and with others filled out in exotic detail. The more conservative Hamlet-worlds are the ones with which Shakespeare would have been most comfortable. The RG-worlds are exotic Hamlet-worlds, and most Hamlet-worlds are not RG-worlds.

** This connects nicely to the previous entry. The asymmetry turns out to have a deeper importance, in a way I had not considered. The argument could have gone like this: (1) A theory is associated with a set of models/worlds. (2) A theory is a story. (3) Therefore, a story is associated with a set of worlds rather than with a single world.

Last May, Carl Sachs asked me what I thought the difference was between a story and a theory. I replied along these lines: A story specifies what its world is like. A theory conjectures what our world is like. Put differently, a theory is a story which we take to be about our actual world.

It now occurs to me that there is an asymmetry between familiar philosophical accounts of stories and of theories: One talks of a story specifying a single world. One asks: What is it like in Sherlock Holmes' London? Of course, the answer cannot be entirely determinate. There are things that the story does not tell us.

According to the semantic conception of theories, a theory can be identified with its models. One might say that the theory is the set of worlds that behave in accord with the theory. The theory is right if the actual world is one of the worlds in that set.

So we are tempted to say that there is the world described by the Holmes stories, although it is described incompletely, but there are many worlds specified when specifying a scientific theory. This difference may simply be superficial. If it is not, then either: (A) A theory is not a story; or (B) it is wrong to think of a theory as the set of its models.

(I suspect the difference is superficial. That, after all, is why this is mentioned in a blog rather than in a paper.)